Husain, Kabir - National Centre for Biological Sciences, Tata Institute of Fundamental Research

Dynamics of Emergent Structures in an Active Polar Fluid

Inspired by recent evidence that the actomyosin cortex templates the organisation of certain cell surface proteins, here we construct an active fluid description of actin filaments and myosin motors. We study the nucleation and form of compact structures that arise spontaneously in this description. Elastic forces, self-propulsion and contractility give rise to a phase diagram of various localised defect configurations, some of which are mobile. We explore their kinetics as well as the dynamics of interacting structures. Finally, we discuss some implications for the study of the cell surface.